Perl Tutorials - Herong's Tutorial Examples - Version 5.30, by Dr. Herong Yang

Symbolic (or Soft) References

This chapter provides tutorial examples and notes about symbolic (or soft) references. Topics include replacing variable or function identifiers with string expressions in curly brackets {}; using scalar variables without {}; using the dereference operator -> with array, hash, or function subscription: EXPR->[*], EXPR->{*}, or EXPR->(*).

Using Symbolic References

$$name - Replacing Identifiers by Scalar Variables

${EXPR} - Replacing Identifiers by Expressions

EXPR->* - The Dereference Operator

$$$name - Nested Symbolic References

Table of Contents

 About This Book

 Perl on Linux Systems

 ActivePerl on Windows Systems

 Data Types: Values and Variables

 Expressions, Operations and Simple Statements

 User Defined Subroutines

 Perl Built-in Debugger

 Name Spaces and Perl Module Files

Symbolic (or Soft) References

 Hard References - Addresses of Memory Objects

 Objects (or References) and Classes (or Packages)

 Typeglob and Importing Identifiers from Other Packages

 String Built-in Functions and Performance

 File Handles and Data Input/Output

 Open Files in Binary Mode

 Open Directories and Read File Names

 File System Functions and Operations

 Converting Perl Script to Executable Binary

 Using DBM Database Files

 Using MySQL Database Server

 Socket Communication Over the Internet

 XML::Simple Module - XML Parser and Generator

 XML Communication Model

 SOAP::Lite - SOAP Server-Client Communication Module

 Perl Programs as IIS Server CGI Scripts

 CGI (Common Gateway Interface)

 XML-RPC - Remote Procedure Call with XML and HTTP

 RPC::XML - Perl Implementation of XML-RPC

 Integrating Perl with Apache Web Server

 CGI.pm Module for Building Web Pages

 LWP::UserAgent and Web Site Testing

 References

 Printable Copy - PDF Version

Symbolic (or Soft) References - Updated in 2014, by Dr. Herong Yang